/// <summary>
/// 分页查询并转换到仓储DTO对象
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <typeparam name="DtoTEntity"></typeparam>
/// <param name="queryable"></param>
/// <param name="pageModel"></param>
/// <returns></returns>
//public static PagedResultDto<TEntity> GetPagingData<TEntity>(this IQueryable<TEntity> queryable, PagingDto pageModel)
public static PagedResultDto <DtoTEntity> GetPagingData <TEntity, DtoTEntity>(this IQueryable <TEntity> queryable, PagingDto pageModel)
{
queryable = queryable.ApplySorting(pageModel);
var pagedResultDto = queryable.BuildPaging(pageModel);
#region 射对象
//构建返回对象
List <DtoTEntity> data = new List <DtoTEntity>();
//由于该分页扩展类是静态对象,因此此处单独初始化映射关系进行对象的转换
var config = new MapperConfiguration(cfg => cfg.CreateMap <TEntity, DtoTEntity>());
var mapper = config.CreateMapper();
foreach (var item in pagedResultDto.Items)
{
data.Add(mapper.Map <TEntity, DtoTEntity>(item));
}
PagedResultDto <DtoTEntity> pagedResultDestination = new PagedResultDto <DtoTEntity>(pagedResultDto.TotalCount, data);
#endregion
return(pagedResultDestination);
//该方案由于Abp库的扩展函数已过时不推荐使用
//var data = pagedResultDto.Items.MapTo<List<DtoTEntity>>();
//return new PagedResultDto<DtoTEntity>(pagedResultDto.TotalCount, data);
}
/// <summary>
/// 创建分页表达式,并且获取封装数据对象
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="queryable"></param>
/// <param name="pageModel"></param>
/// <returns></returns>
private static PagedResultDto <TEntity> BuildPaging <TEntity>(this IQueryable <TEntity> queryable, PagingDto pageModel)
{
//构建分页查询
var quer = queryable.Skip(pageModel.SkipCount).Take(pageModel.MaxResultCount);
//返回数据集合(触发数据库查询)
var dataList = quer.ToList();
//返回数据总条数(触发数据库查询)
var dataCount = queryable.Count();
return(new PagedResultDto <TEntity>(dataCount, dataList));
}
/// <summary>
/// 设置分页
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="queryable"></param>
/// <param name="pageModel"></param>
/// <returns></returns>
private static IQueryable <TEntity> ApplySorting <TEntity>(this IQueryable <TEntity> queryable, PagingDto pageModel)
{
if (!pageModel.Sorting.IsNullOrWhiteSpace())
{
//设置提供的排序字段
queryable = queryable.OrderBy(pageModel.Sorting);
}
else
{
//设置默认排序字段
var p = typeof(TEntity).GetProperty("Id");
if (p != null)
{
queryable = queryable.OrderBy("Id");
}
}
return(queryable);
}
/// <summary>
/// 累加分页信息
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="queryable"></param>
/// <param name="pageModel"></param>
/// <returns></returns>
private static IOrderedQueryable <TEntity> ApplyThenSorting <TEntity>(this IOrderedQueryable <TEntity> queryable, PagingDto pageModel)
{
//累加排序字段
if (!pageModel.Sorting.IsNullOrWhiteSpace())
{
queryable = queryable.ThenBy(pageModel.Sorting);
}
return(queryable);
}
/// <summary>
/// 分页查询到实体对象
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="queryable"></param>
/// <param name="pageModel"></param>
/// <returns></returns>
public static PagedResultDto <TEntity> GetPagingData <TEntity>(this IOrderedQueryable <TEntity> queryable, PagingDto pageModel)
{
queryable = queryable.ApplyThenSorting(pageModel);
return(queryable.BuildPaging(pageModel));
}